Railway-traffic-controlling apparatus



Jan. 24, 1928.

s. M. LUCAS RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Sept. 14. 1926 1 INVENTQR:

Patented Jan. 24, 1928.

UNITED STATES rnrsur OFFICE.

SAMUEL M. LUGAS, ,QF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SEVISSVALE, PENNSYLVANIA, A COR EORATION OF PENNSYLVANIA.

RAILWAY-TRAFFIG-CONTROLLING APPARATUS;

Application filed September 14, 1926.

My invention relates to railway traffic controlling apparatus, and particularly to apparatus of the type comprising governing The accompanying drawing is a diagrammatic view showing one form of apparatus embodying my lnvention.

Referrmg to the drawlng, the reference characters 1 and 1 designate the track rails of a railway along which tratlic normally movesin the direction indicated by the arrow. These rails are divided by insulated joints 2 into track sect-ions of which two sections CD and D--E are shown in the drawing. Each section is provided as usual with a track circuit comprising a battery 4 connected across the rails at the exit end of the section, and a track relay connected across the rails at the entrance end of the section and designated by the reference character R with an exponent corresponding to the location.

Each section is also provided with means for supplying train governing current to the track rails, this means in the form here shown being a transformer designated by the reference character F- with an exponent corresponding to the location, and having its secondary 3 connected across the rails at the exit end of the section in series with the track batteryd' and a limiting reactance 5, The primary 6 of transformer F is at times supplied with current from a transformer H which in turn is supplied with current from a transformer J the primary of which is constantly supplied with alternating current from a suitable source not shown in the drawing. The circuit for the primary 6 of transformer F is from the secondary '7 of transformer H through primary 6,

front contact 13 of track relay R front contact 1d of achecliing relay X to secondary 7. It will be seen, therefore, that train governing current will be supplied to the rails of secti0nD-E when and only when track Serial No. 135,347.

relay E is energized, that is, when and only when section CD is unoccupied.

The circuit for primary 8 of transformer I-f includes the secondary 9 of the transformer J and a trackway loop L This loop involves two conductors extending parallel with the trackrails at the junction be. tween sections (1-D and D-E, which conductors extend a short distance into each section. In the form here shown, the loop L is constantly energized from the secondary 9 of transformer J.

The apparatus thus far described is intended for co-operatio-n with train-carried governing mechanism in such way that when the train is in a section of track which is supplied with train governing current the train may proceed without retardation, but that when the train is in a, section of track avliicli is not supplied with train governing current an automatic application of the brakes will be incurred unless the engineer acknowledges, that is, unless he takes suitable action to indicate that he is alive and alert.

The loop L has two functions. First, as suming that section OD is occupied,.so that section DE is not supplied with train governing current, and-assuming that the engineer of the following train has acknowledged upon enteringsection DE.

the train-carried mechanism will be momentarily energized upon passingover the loop L thus requiring a second acknowledgment as soon as the train enters the occupied section C--D. For this reason-the loop L is referred to as a recurrent acknowledgement loop. Second, it will be noted that the insulated joints 2 at the point D are staggered, so that when sections C-D and D--E are both supplied with train-governing current,

a train might receive a momentary stop in dication at the point D while the receiving apparatus on the train is passing over the space between joint 2 in rail 1 and joint 2 in rail [1. This momentary indication is prevented by the loop L which,of course, supplies train governing current to the receiving apparatus while i between these two joints.

If the conductors of the loop L should lit tu-cidcntall i' maize electrical contact with one or both oi the track rails, they might transtcr t circuit energy from section CD to i m D-E or vice versa, or they might teed train governing energy into the track ran and thereby falsely energize the rcceivinc. apiiaratus on a train. To prevent this. I have providcd means for detecting accidental contact of the loop L with a track rail. For this purpose an auxiliary secondary ll on translomucr lis connected With the loop L and ith gr 'ounrl G Whereas the uni;- iliary re 1y 1:? is connected with the loop l) a -l with ground at G. A resistance l2 it interposed hetuccn secondary ll. and the around U to limit the current from this secondary to a value just sullicient to liieep relay It energized. In the event 01 contact lactwcen loop L and one of the track railsrsonie oi": the current from secondary 11 Willbe shunted around relay It, so that this relay will open it being; understood that the electrical connection between the track rail and the ground through the ties and ballast is of reasonably low resistai'ice. In the event of relay X opening, contact l t ofthis relay will open the primary circuit for transl'orincr F and so will discontinue the supply of train governing current to the rails of section lk-l5. A train entering this section will theretorereceiye a stop indication.

As here shown, each section provided with a signal designated by the reference character S, with an exponent corresponding to the location. Referring to signal S, the circuit tor this signal passes from the terminal B of a suitable source of current,

through front contact 15 0t relay K front contact 16 of track relay R and the operating mechanism tor signal S to termi 11:11 O ot 'the same source of current. lt-ie lay 11 becomes opened, signal S will indicate stop, and signal S will, of course, indicate caution, thereby giving further indication oi the improper condition of the traclnvay loop L Although I have herein shown and described only one term oi apparatus embodying my invention, it is understood that various changes and modifications may be made therein Within the scope of the up pended claims without departing from the spirit and scope or my invention.

Having thus described my invention What I A claim is cidental contact of said auxiliary apparatus with a track rail.

2.111 coinlnnation, a stretch of railway track, means controlled by tratlic conditions for each tioned i nstrinnentalitics 0 :t'or supplying train governing energy to the track rails a cmnluctor located in thc traclircay for also supplying covering en orgy to trains, and means for preventing the supply o't en the tract: rails l the event of incidental coin tact ol raid conductor with a tract: rail.

3. ln combination, a Elllt'ttfll ot' railway lracl: incair" controlled hy trallic conditiom tor :iupnl train ,u'oi'crniiur energy to the lrai-h rails; a coiulucun' located in the truclinuiy For alro supplying 'oi'ernint energy to trainsg a source of current: conncclcd luatu'ccn said conductor and ground, and a relay alto connectedlwtwcen said conthwtur and ground tor controlling Eiuiil supply of energy to the tract: rails.

i. In icoin'liination. a stretch oi railway trucln a recurrent aclcnovrledgmenl loop lo' cated in the tracliwny for supplying; gov erning energy to trains, a source ol current connected between said loop and Jround a relay also connected lictween said loop and ground, and a signal controlled by raid rclay.

:1. 1n con'ibinatiou. a stretch oi railway track, incuns controlled by trallic conditions for su iplyiuu train governing cucrptyyto the track rails, a conductor located in the trackway loralso su iiplying u r ircrni11g" energy to trains, a source oi current connected between said conductor and around, a relay also a n (l said supply aid relay,

and a signal controlled by said relay.

In a sysmni conipi sing! a rotch of railway track divided into sections means tion controlled by trattic conditionsinadvance tor supplying l rain govern ing energy to the rails oi the FEE tion, an auxiliary conductor located at the junction of tu'o ad iaccnt sections and extending a short distance into each section for momentarily supplying governing;- enerrry to trains when the supply ot train uo'vcrniiur cner c 'itothc track rain; has been diurumtinuetl and lo:- prevcntinp; momentary interriuption of the supply otenergy as strain pas as tronione section to the other wuile train governing energy is being supplied to the ails of each section; the combination with the atoreinern tincans for dctccb ing accidental contact of said conductor with a track rail.

7.111 a system coniprisii'iu' a stretch of railway track divided into sections means tor each section controlled by trafllc conditions in advance tor supplying train governing energy to the rails of the section, an auxiliary conductor located at the junction of two adjaccnt sections and extending a short distance into each section for 1no-- nientarily supplying goycrnii'ig energy to trains when the supply 0t train governing l'roin said lirst source to liltl llll) energy to the track rails has been discontinued and for preventing momentary interruption of the supply of energy as a train passes from one section to the other while train governing energy is being supplied to the rails of each section; the combination with the aforementioned instrumentalities of a source of current connected between said conductor and ground, a relay also connected between said conductor and ground, and means for controlling the supply of train governing energy to the rear of said two sections by said relay.

8. Railway traffic controlling apparatus comprising recurrent acknowledgment loops located in the trackway, and means for detecting accidental contact of one of said loops with a track rail.

9. Railway traffic controlling apparatus comprising means for supplying train governing energy to the track rails a recurrent acknowledgment loop located in the tackway, an auxiliary source of current connected between said loop and ground, and an auxiliary relay connected between said loop and ground for controlling the supply of train governing energy to the track rails.

In testimony whereof I aifix my signature.

SAMUEL M. LUCAS. 

